By Live 5 News Web Staff and Liza Lucas| April 24, 2017 at 7:26 AM EST - Updated July 11 at 4:50 PM

(Source: WCSC)

(Source: City of Charleston)

(Source: WCSC)

CHARLESTON, SC (WCSC) - If you drove through flood waters Monday, you know how badly the city of Charleston needs drainage work done.

The intersection of Cannon Street and President closed this week as crews began the largest project to alleviate flooding in the city's history — the Spring and Fishburne Drainage Improvement Project.

The closure is expected to last approximately one month, according to a news release.

"The closure of the intersection of Cannon and President Streets is necessary for everyone's safety as construction of a critical component for long-term drainage relief in the area is completed," City of Charleston Senior Engineering Project Manager Steven Kirk said. "We will work hard to ensure the intersection is reopened as soon as possible."

The project affects around 20 percent of the Charleston peninsula, including MUSC, Roper, the Citadel and VA hospital.

"The Spring and Fishburne drainage project is one of the largest upgrades to our drainage system on the peninsula," John Martin, senior advisor to Mayor Tecklenburg said. "If you can imagine an underground web of things — dating some from the 1800s, some from the 1900s — we're trying to pull all these pieces and parts together."

During a five-phase, $146 million dollar process, new systems will be added to collect rainwater as well as new underground tunnels and a pump station to move water out. The project is one of many across the city to address problematic flooding.

"It's kind of the rubix cube of infrastructure," Martin added. "Hopefully we'll have all the colors on one side so people can get back to normal life."